ZnO/EP复合材料的制备及其导热性能

采用溶胶-凝胶法制备纤锌矿型氧化锌(zinc oxide,ZnO)粉体,考察了煅烧温度对ZnO粉体质量的影响;将不同煅烧温度获得的ZnO填充于环氧树脂(epoxy resin,EP)得到系列ZnO/EP复合材料,采用红外光谱仪(Fourier transform infrared spectroscopy,FTIR)和场发射扫描电子显微镜(field emission scanning electron microscope,FESEM)对ZnO/EP复合材料进行结构和形貌表征,研究了ZnO粉体粒径及填充量对ZnO/EP复合材料导热性能的影响。结果表明,ZnO粉体粒径随煅烧温度升高而增大,其中700 ℃下制得的ZnO粉体粒径最大且纯度高。当ZnO填充量一定时,ZnO粉体粒径越大,越有利于提升ZnO/EP复合材料的导热性能;随ZnO填充量的增加,ZnO/EP复合材料的热导率不断提高,当ZnO体积分数为30.05%时,复合材料热导率达到0.54 W/(m·K),较纯环氧树脂提高了184%,且保持良好的力学性能。

Preparation and Thermal Conductivity of ZnO/EP Composites

The wurtzite ZnO powders were prepared by the sol-gel method, and the influence of calcination temperature on the quality of ZnO powder was investigated. ZnO as-prepared at different calcination temperatures was filled in epoxy resin (EP) to obtain a series of ZnO/EP composites. The structure and morphology of ZnO/EP composites were characterized and analyzed using FTIR and FESEM. The effects of ZnO particle size and content on the thermal conductivity of ZnO/EP composites were studied. The results show that the higher the calcination temperature is, the bigger the particle size of ZnO is. Specifically speaking, ZnO powder prepared at 700 ℃ has the largest particle size and highest purity. Moreover, when the content of ZnO is fixed, ZnO powder with bigger particle size is conducive to improving the thermal conductivity of ZnO/EP composites. With the content of ZnO increasing, the thermal conductivity of ZnO/EP composites continues to increase. When the volume fraction of ZnO is 30.05%, the thermal conductivity of ZnO/EP composites achieves 0.54 W/(m·K), which is 184% higher than that of pure epoxy, and the mechanical property is still maintained at a good level.